CN102156168A - Bridge prestressing force pore path grouting defect detection method - Google Patents
Bridge prestressing force pore path grouting defect detection method Download PDFInfo
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- CN102156168A CN102156168A CN 201110052444 CN201110052444A CN102156168A CN 102156168 A CN102156168 A CN 102156168A CN 201110052444 CN201110052444 CN 201110052444 CN 201110052444 A CN201110052444 A CN 201110052444A CN 102156168 A CN102156168 A CN 102156168A
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Abstract
The invention discloses a method for detecting the prestressing force pore path grouting quality of a prestressing force concrete bridge. The method comprises the following steps: respectively arranging two detectors at the two ends of a prestressing force pore path; exciting one end of the prestressing force pore path to generate shock waves; respectively recording a scattered wave and a transmitted wave in the prestressing force pore path by the two detectors at the two ends; carrying out modal identification on the transmitted wave; carrying out time-frequency analysis on the scattered wave; carrying out migration imaging by using the modal of the transmitted wave; and carrying out defect identification by using a migration image. By the method provided by the invention, the properties, scale and position of the grouting defect can be reliably determined by combining time frequency analysis which is an unsteady-state signal analysis technology with a migration imaging technology, based on a sound wave scattering technology and deep understanding on the internal elastic wave vibration characteristics of a bridge body.
Description
Technical field
The present invention relates to concrete-bridge construction quality detection range, be primarily aimed at the detection of prestressed pore passage grouting quality in the post-stressed bridge.
Background technology
In railway, highway construction, more and more Prestressed Concrete Bridges that adopt.Prestressed Concrete Bridges is by exerting pressure to the tensile region in advance, reduces or offsets the caused tension of load, thereby postpone the appearance of distress in concrete and carry out, and improved the cracking resistance and the rigidity of bridge greatly.Present most of prestress bridge adopts post-tensioned construction, promptly first casting concrete, wait to reach design strength 75% or more after again prestressed reinforcement of tensioning with formation prestress.Use metal or plastic film capicitor and form 1 pipeline when building member in concrete, deformed bar therefrom passes.Treat with concrete this pipeline to be filled with again after the deformed bar stretch-draw.This pipeline is exactly a prestressed pore passage, claims corrugated tube again.
The problem that the grouting quality in duct exists is commonplace, mainly is to come to nothing and water-filling.Professor R.H.EVANS of Switzerland university observes grout bleeding in the prestress pipe and the problem of the free water that forms the earliest, Britain also finds to seal up for safekeeping in the grouting pipe problem (white poplar of air and water-filling in bridge detects, " grouting and the performance impact analysis of stretching force " to prestress alkali beam, the Maritime Affairs University Of Dalian, Master's thesis).The length of coming to nothing of finding duct slip casting in recent years bridge detects accounts for the 10-20% that detects length, some disease bridge come to nothing the district length in addition account for 30%, and common pipeline water-filling phenomenon.The not full meeting of slip casting causes the corrosion rust of prestress wire disconnected, and loss of prestress and stress are concentrated, and have a strong impact on structure durability, even causes structural failure or collapse.Water-filling can quicken the corrosion of steel strand wires in the pipeline, also can bring out the frost heave disease at north cold area, and the infringement protective seam quickens reinforcing bar and steel strand wires corrosion.
It is in 2007 that China's early start detects the duct grouting quality, adopt radar method in Chongqing and Yunnan expressway construction, to carry out successful Application (Xu Jingmiao by Zhao Yonggui, Ai Jianqiang, the integral prefabricated quality control on construction main points of Transbay Bridge, Qingdao 60m prestressed concrete box girder [J], highway, 2009, No.9 136-141).Yet radar only limits to plastic film capicitor, because electromagnetic wave can't penetrate, radar method is invalid for metallic bellows.People such as Zou Chunjiang etc. and Wang Zhifeng once was duct grouting quality test experience (Zou Chunjiang with the impact echo method, Chen Zhengzhou, Dong Ping, Cao Dongfang, Wu Yongjing. the impact echo dominant frequency is to the response and the application [J] of box girder pre-stressed duct slip casting plumpness, highway communication science and technology, 2010,27 (1): 73-77; Wang Zhifeng, Zhou Xianyan, Yan Banfu, Xiao Yunfeng, the impact echo method detects prestress beam hole pipeline pneumatic mortar quality [J], vibration and impact, 2009, VoL.28, No.1,166-169).Impact echo method (IE:Impact-Echo Method) is concrete quality detection method (the Mary J.Sansalone that was once proposed by Cornell Univ USA the earliest, William B.Streett, The Impact-Echo Method[J]. NDTnet, 1998,3:(2) February), its principle be utilize impact echo between the concrete component upper and lower interface repeatedly reflect to form resonance, infer distance between the interface by measuring resonant frequency and medium velocity of wave.According to the impact echo law theory,, can produce the resonance echo that frequency is higher between empty and last interface, than the resonant frequency height of beam slab upper and lower interface correspondence if the cavity is arranged in the duct.Yet experiment shows that the resonant frequency of the impact echo that the pipeline cavity is corresponding is not only not high, reduces on the contrary, and the phenomenon of a plurality of frequency peak occurred, and contradiction has taken place the principle that this and IE method rely on resonant frequency just to infer interface depth.Thereby run into puzzlement with the effort that the IE method detects the corrugated tube grouting quality.In addition, other detection methods for example ultrasound tomography method, infra-red thermal imaging method etc. owing to reasons such as observation condition and resolution, also powerless to the detection of inside, duct grouting quality.
Summary of the invention
Technical matters to be solved by this invention provides a kind of bridge prestress pore channel slip casting defect inspection method to overcome the problem that above-mentioned IE method, ultrasound tomography method, infra-red thermal imaging method etc. can't effectively detect the duct grouting quality.
The present invention is for solving the problems of the technologies described above, and the bridge prestress pore channel slip casting defect inspection method that provides may further comprise the steps:
Step 1: any end at prestressed pore passage excites elastic wave, measures the scattering wave and the transmitted wave at described prestressed pore passage two ends simultaneously;
Step 2: described transmitted wave is carried out the temporal frequency spectrum that time frequency analysis calculates described transmitted wave, and the temporal frequency that goes out the seismic phase of all different modalities in the described transmitted wave according to the spectrum energy size identification distributes;
Step 3: described scattering wave is carried out the temporal frequency spectrum that time frequency analysis obtains described scattering wave, and described scattering wave is offset collection of illustrative plates after stack obtains being offset stack according to the mode in the described transmitted wave, according to the defective in the described prestressed pore passage of figure spectrum energy size identification after the skew stack.
Beneficial effect of the present invention is: adopt the sound scattering technology, on the basis of fully understanding beam body inner elastomeric ripple vibrations characteristics, take this unstable signal analytical technology of time frequency analysis, the complex vibration of propagating in beam slab and prestressed pore passage is carried out pattern decomposes, identify the Lame ripple of compressional wave, shear wave and various mode, and information such as amplitude of these different modalities Lame ripple, phase place.In conjunction with migration and imaging techniques, can determine the position of slip casting defective reliably simultaneously.
On the basis of technique scheme, the present invention can also do following improvement.
Further, in the step 1,2 wave detectors are arranged on the anchor head at described prestressed pore passage two ends, excite the generation elastic wave at an end of prestressed pore passage.
Further, in the step 1, be positioned at the wave detector that excites elastic wave one end of prestressed pore passage, be used to write down the scattering wave in the described duct; Be positioned at the wave detector of the other end, be used to write down the transmitted wave in the described prestressed pore passage.
Description of drawings
Fig. 1 is the process flow diagram of bridge prestress pore channel grouting quality detection method of the present invention;
Fig. 2 is the collection in worksite synoptic diagram of bridge prestress pore channel grouting quality detection method of the present invention;
Fig. 3 is the analysis process flow diagram of bridge prestress pore channel grouting quality detection method of the present invention;
Fig. 4 is a time-frequency result of calculation in the inventive method confirmatory experiment.
In the accompanying drawing, the list of parts of each label representative is as follows:
1, main frame, 2, first detector, 3, second detector, 4, explosive source, 5, prestressed pore passage, 6 first data lines, 7, second data line, 8, trigger line.
Embodiment
Below in conjunction with accompanying drawing principle of the present invention and feature are described, institute gives an actual example and only is used to explain the present invention, is not to be used to limit scope of the present invention.
As shown in Figure 1, the concrete steps of bridge prestress pore channel grouting quality detection method of the present invention comprise:
Step 1: any end at prestressed pore passage excites elastic wave, measures the scattering wave and the transmitted wave at described prestressed pore passage two ends simultaneously;
Step 2: described transmitted wave is carried out the temporal frequency spectrum that time frequency analysis calculates described transmitted wave, and the temporal frequency that goes out all different modalities seismic phases in the described transmitted wave according to temporal frequency spectrum energy size identification distributes;
Step 3: described scattering wave is carried out the temporal frequency spectrum that time frequency analysis obtains described scattering wave, and described scattering wave is offset collection of illustrative plates after stack obtains being offset stack according to the mode in the described transmitted wave, according to the defective in the described prestressed pore passage of figure spectrum energy size identification after the skew stack.
Wherein, in step 1,2 wave detectors are arranged on the anchor head at described prestressed pore passage two ends, excite the generation elastic wave at an end of prestressed pore passage; Be positioned at the wave detector that excites elastic wave one end of prestressed pore passage, be used to write down the scattering wave in the described prestressed pore passage; Be positioned at the wave detector of the other end, be used to write down the transmitted wave in the described prestressed pore passage.
Method of the present invention mainly comprises collection in worksite and two parts of Data Processing in concrete enforcement.
Fig. 2 is the collection in worksite synoptic diagram of duct of the present invention grouting quality detection method.The hardware device that needs when the inventive method detects comprises main frame 1, first detector 2, second detector 3 and explosive source 4, wherein, first detector 2 and second detector 3 are installed on the two ends of prestressed pore passage 5 respectively, first detector 2 links to each other with main frame 1 by first data line 6, second detector 3 links to each other with main frame 1 by second data line 7, and explosive source 4 is arranged at the end that prestressed pore passage 5 is positioned at second detector 3, and links to each other with main frame 1 by triggering line 8.The key step of collection in worksite comprises:
(1) first detector 2 and second detector 3 are bonded in respectively on the anchor head at prestressed pore passage 5 two ends;
(2) utilize explosive source 4 to excite the generation vibration wave (in Fig. 2 on an anchor head therein, explosive source 4 is arranged on prestressed pore passage 5 to be positioned at second detector 3 one ends and to excite the generation shock wave), mode of excitation can adopt common iron hammer hammering, also can adopt special-purpose hammering focus.
(3) as shown in Figure 2, utilize the scattering wave that produces in the second detector 3 record prestressed pore passages 5, utilize the transmitted wave that produces in the first detector 2 record ducts 5.
Fig. 3 is an analysis flow process of the present invention.Its key step comprises:
(1) transmitted wave is carried out after time frequency analysis calculates the temporal frequency spectrum of transmitted wave the time and the frequency distribution that go out different modalities according to the spectrum energy size identification;
(2) scattering wave is carried out the temporal frequency spectrum that time frequency analysis calculates scattering wave;
(3) distribute and carry out migration imaging according to distribute temporal frequency to scattering wave of the temporal frequency of the mode of transmitted wave, distribute respectively temporal frequency with the transmitted wave different modalities of the temporal frequency that is about to scattering wave distributes after the stack, obtains new temporal frequency distribution spectrogram;
(4) carry out defect recognition according to the size of spectrum energy in the migrated image, promptly energy the greater is judged to be defective.
Experimental verification
The beam slab model of an at first prefabricated band prestressed pore passage detects then in the test, at last prestressed pore passage is opened checking.Empirical tests, testing result and actual result degree of conformity reach more than 90%.Detailed process is as follows.
1, prefabricated model length is 11 meters, wherein default 1 prestressed pore passage, built-in reinforcing bar.
2, testing process: arrange wave detector at the prestressed pore passage two ends, wherein a termination is received scattering wave, and the other end receives transmitted wave, excites with hammering at reception scattering wave end; Under same coupling condition, knock more than 3 times during detection, to guarantee the testing result repeatability.
3, detection is after Data Processing obtains result as shown in Figure 4, and it is as follows to identify defective:
The defect recognition presentation of results:
The defective that time-frequency result of calculation shows is 7, but wherein 5 a little less than, 2 are strong and continuously in flakes, therefore are shown as 2 defectives in defect map.Belong to hammering influence band on the left of among the time-frequency figure in 0.5 meter, energy signal wherein should not be judged to be defective.
4, damaged checking
For checking testing result correctness, after detection finishes, model is broken checking.Through field staff's observation, obtain following actual defects result:
5, testing result and measured result comparative analysis
The defective locations of checking among the result is slightly different with testing result with length, after the influence of eliminating model defect method for making, testing result with actual be very consistent.
Above-mentioned description of test adopts bridge prestress pore channel grouting quality detection method of the present invention, can determine the position of slip casting defective reliably.
The above only is preferred embodiment of the present invention, and is in order to restriction the present invention, within the spirit and principles in the present invention not all, any modification of being done, is equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (3)
1. bridge prestress pore channel grouting quality detection method, step comprises:
Step 1: any end at prestressed pore passage excites elastic wave, measures the scattering wave and the transmitted wave at described prestressed pore passage two ends simultaneously;
Step 2: described transmitted wave is carried out the temporal frequency spectrum that time frequency analysis calculates described transmitted wave, and the temporal frequency that goes out all different modalities seismic phases in the described transmitted wave according to temporal frequency spectrum energy size identification distributes;
Step 3: described scattering wave is carried out the temporal frequency spectrum that time frequency analysis obtains described scattering wave, and described scattering wave is offset collection of illustrative plates after stack obtains being offset stack according to the mode in the described transmitted wave, according to the defective in the described prestressed pore passage of figure spectrum energy size identification after the skew stack.
2. according to the described method of claim 1, it is characterized in that:
In the step 1,2 wave detectors are arranged on the anchor head at described prestressed pore passage two ends, excite the generation elastic wave at an end of prestressed pore passage.
3. according to the described method of claim 2, it is characterized in that:
In the step 1, be positioned at the wave detector that excites elastic wave one end of prestressed pore passage, be used to write down the scattering wave in the described prestressed pore passage; Be positioned at the wave detector of the other end, be used to write down the transmitted wave in the described prestressed pore passage.
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102507743A (en) * | 2011-11-03 | 2012-06-20 | 北京星通联华科技发展有限公司 | Nondestructive testing method of bridge prestressed duct grouting compactness |
| CN103245728A (en) * | 2013-05-09 | 2013-08-14 | 彭凯 | Holographic identification method and system for flaw damage of bridge |
| CN103940914A (en) * | 2013-10-28 | 2014-07-23 | 湖南省交通科学研究院 | Method for manufacturing calibration model of pipeline grouting quality detection instrument and calibration model |
| CN106124622A (en) * | 2016-06-12 | 2016-11-16 | 中国十七冶集团有限公司 | A kind of prestress pore passage dense degree integrated evaluating method based on sound scattering technology |
| CN107894459A (en) * | 2017-11-09 | 2018-04-10 | 四川陆通检测科技有限公司 | Prestress hole path pressure grouting compactness method of testing based on fluctuation signal signature analysis |
| CN108844856A (en) * | 2018-07-04 | 2018-11-20 | 四川升拓检测技术股份有限公司 | Based on elastic impact wave and the sleeve of machine learning grouting defect lossless detection method |
| CN108918660A (en) * | 2018-05-19 | 2018-11-30 | 徐光大 | The lossless detection method of the sleeve grouting plumpness of reinforced bar sleeve grouting jointing |
| CN109840891A (en) * | 2019-01-07 | 2019-06-04 | 重庆工程学院 | A kind of intelligence strand tapered anchorage and prestressed monitoring method and detection system, terminal |
| CN110007007A (en) * | 2019-04-09 | 2019-07-12 | 湖南普奇地质勘探设备研究院（普通合伙) | A kind of detection method and device of bellows slip casting plumpness |
| CN110045016A (en) * | 2019-04-24 | 2019-07-23 | 四川升拓检测技术股份有限公司 | A kind of tunnel-liner lossless detection method based on audio analysis |
| CN110455917A (en) * | 2019-08-22 | 2019-11-15 | 福建博海工程技术有限公司 | A kind of repairing concrete crack quality determining method |
| CN111413739A (en) * | 2020-04-16 | 2020-07-14 | 成都农业科技职业学院 | Method for detecting grouting defect of bridge stress pipeline based on ground penetrating radar method |
| CN112229915A (en) * | 2020-12-11 | 2021-01-15 | 四川升拓检测技术股份有限公司 | Device and method for measuring grouting compactness of prestressed duct |
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| CN102507743A (en) * | 2011-11-03 | 2012-06-20 | 北京星通联华科技发展有限公司 | Nondestructive testing method of bridge prestressed duct grouting compactness |
| CN103245728A (en) * | 2013-05-09 | 2013-08-14 | 彭凯 | Holographic identification method and system for flaw damage of bridge |
| CN103245728B (en) * | 2013-05-09 | 2015-04-08 | 彭凯 | Holographic identification method and system for flaw damage of bridge |
| CN103940914A (en) * | 2013-10-28 | 2014-07-23 | 湖南省交通科学研究院 | Method for manufacturing calibration model of pipeline grouting quality detection instrument and calibration model |
| CN106124622B (en) * | 2016-06-12 | 2019-01-22 | 中国十七冶集团有限公司 | A kind of prestress pore passage dense degree integrated evaluating method based on sound scattering technology |
| CN106124622A (en) * | 2016-06-12 | 2016-11-16 | 中国十七冶集团有限公司 | A kind of prestress pore passage dense degree integrated evaluating method based on sound scattering technology |
| CN107894459A (en) * | 2017-11-09 | 2018-04-10 | 四川陆通检测科技有限公司 | Prestress hole path pressure grouting compactness method of testing based on fluctuation signal signature analysis |
| CN108918660B (en) * | 2018-05-19 | 2020-12-25 | 徐光大 | Nondestructive detection method for sleeve grouting fullness of steel bar sleeve grouting connection joint |
| CN108918660A (en) * | 2018-05-19 | 2018-11-30 | 徐光大 | The lossless detection method of the sleeve grouting plumpness of reinforced bar sleeve grouting jointing |
| CN108844856A (en) * | 2018-07-04 | 2018-11-20 | 四川升拓检测技术股份有限公司 | Based on elastic impact wave and the sleeve of machine learning grouting defect lossless detection method |
| CN108844856B (en) * | 2018-07-04 | 2023-08-15 | 四川升拓检测技术股份有限公司 | Sleeve grouting defect nondestructive testing method based on impact elastic wave and machine learning |
| CN109840891A (en) * | 2019-01-07 | 2019-06-04 | 重庆工程学院 | A kind of intelligence strand tapered anchorage and prestressed monitoring method and detection system, terminal |
| CN110007007A (en) * | 2019-04-09 | 2019-07-12 | 湖南普奇地质勘探设备研究院（普通合伙) | A kind of detection method and device of bellows slip casting plumpness |
| CN110045016A (en) * | 2019-04-24 | 2019-07-23 | 四川升拓检测技术股份有限公司 | A kind of tunnel-liner lossless detection method based on audio analysis |
| CN110455917A (en) * | 2019-08-22 | 2019-11-15 | 福建博海工程技术有限公司 | A kind of repairing concrete crack quality determining method |
| CN111413739A (en) * | 2020-04-16 | 2020-07-14 | 成都农业科技职业学院 | Method for detecting grouting defect of bridge stress pipeline based on ground penetrating radar method |
| CN112229915A (en) * | 2020-12-11 | 2021-01-15 | 四川升拓检测技术股份有限公司 | Device and method for measuring grouting compactness of prestressed duct |
| CN112229915B (en) * | 2020-12-11 | 2021-03-09 | 四川升拓检测技术股份有限公司 | Device and method for measuring grouting compactness of prestressed duct |
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Effective date of registration: 20160919 Address after: 100191 room 2, building 2, Huayuan Road 1112, Haidian District, Beijing, China Patentee after: BEIJING TONGDU ENGINEERING GEOPHYSICS LTD. CORP. Address before: 100101, room 1706, building 5, No. 108 East Fourth Ring Road, Chaoyang District, Beijing Patentee before: Zhao Yonggui |